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451.
Over the course of Australia's Millennium Drought, urban water managers gained more appreciation of householders' willingness and capacities to respond to water shortages and restrictions, including by installing rainwater tanks (RWTs) for watering gardens. How urban water managers regard tanks and tank users gives insight into their understandings of social sustainability, as found in interviews conducted in 2006 and 2010. These also revealed a growing distance between policymakers and water providers pursuing a broader approach to sustainability in their communities. The RWT is considered here as a limit case for paradigms of urban water management: it challenges conventional distinctions (such as provider/consumer) and heralds a new hydropolitics. These challenges are discussed as seven kinds of trouble with tanks: (1) incompatibility with the management model and vision of modernity enshrined in the ideal of centralised provision in control of accredited water experts; (2) anxieties about control and risk aroused by these private on-site facilities and their non-expert users; (3) equivocation over their environmental effects, normally assessed in hydrological terms that downplay the benefits of green streetscapes; (4) inexplicability of their popularity within dominant economically rationalist models of customers; (5) educational effects that exceed rationalist, individualist models of learning and require more socially realistic, culturally intelligent and practice-oriented approaches; (6) generation of enthusiasms that are spurned as threats to rationality instead of harnessed to energise the sustainability journey and (7) community-building effects that are unthinkable within the neoliberal customer paradigm but graspable to water managers through lay concepts like “dinner table conversations”.  相似文献   
452.
A tunable diode laser absorption spectrometer (TDLAS) for formaldehyde atmospheric measurements has been set up and validated through comparison experiments with a Fourier transform infrared spectrometer (FT-IR) in a simulation chamber. Formaldehyde was generated in situ in the chamber from reaction of ethene with ozone. Three HCHO ro-vibrational line intensities (at 2909.71, 2912.09 and 2914.46 cm-1) possibly used by TDLAS were calibrated by FT-IR spectra simultaneously recorded in the 1600-3200 cm-1 domain during ethene ozonolysis, enabling the on-line deduction of the varying concentration for HCHO in formation. The experimental line intensities values inferred confirmed the calculated ones from the updated HITRAN database. In addition, the feasibility of stratospheric in situ HCHO measurements using the 2912.09 cm-1 line was demonstrated. The TDLAS performances were also assessed, leading to a 2σ detection limit of 88 ppt in volume mixing ratio with a response time of 60 sec at 30 Torr and 294 K for 112 m optical path. As part of this work, the room-temperature rate constant of this reaction and the HCHO formation yield were found to be in excellent agreement with the compiled literature data.  相似文献   
453.
Cyclone Pam swept through the archipelago of Vanuatu on 13–14 March 2015, with wind speeds exceeding those recorded anywhere in the South Pacific since the 1980s. Southern and central parts of the country were particularly affected. Material damage on Tongoa, one of the most afflicted islands, was extensive, but no deaths were reported. During the storm, villagers found shelter in their kitchen, in what is considered locally as a ‘lifeboat’. The aftermath was managed and mitigated by international aid organisations. On Tongoa, this included a ‘Shelter Cluster’ programme, under which villagers were given house rebuilding kits. Elaborating upon extensive ethnographic investigations on site between 2011 and 2018, this paper explores and reveals the ways in which this aid generated confusion among the local population. In a larger context of regular disasters triggered by natural hazards, locals have found endogenous ways of dealing with such extreme climatic events, for the most part without any external assistance.  相似文献   
454.
Population growth, and hence the population's persistence, is affected by several factors such as climate, species interaction, and harvesting pressure. Proper resource management requires an understanding of these factors. We apply techniques based upon age-structured population matrices to analyze estimated stock sizes derived from annual bottom trawl sampling in the winter feeding area of northeast Arctic cod (Gadus morhua L.) from 1981 to 2003. We run generalized additive models to explain population growth rate by different explanatory variables. Cod population growth was found to be positively related to the abundance of capelin (Mallotus villosus Miller), negatively related to the number of cannibalistic cod with a two-year lag, and marginally positively related to the winter North Atlantic Oscillation index (NAO). This model remains true independently from the population status (i.e., fished or non-fished). Capelin abundance is the main variable that to some degree can be adjusted in order to maintain the population size at a given level of cod harvesting. Our results point to the importance of managing conjointly cod and capelin stocks.  相似文献   
455.
Hormones play a central role in the physiology and behaviour of animals. The recent development of noninvasive techniques has increased information on physical and social states of individuals through hormone measurements. The relationships among hormones, life history traits and behaviours are, however, still poorly known. For the first time, we evaluated natural winter glucocorticoid and testosterone levels in young ungulates in relation to winter progression, diet quality and social rank. Overwinter, levels of glucocorticoid and testosterone decreased, possibly due to the decline of fawns’ body mass. The relationships between hormone levels and diet quality were surprising: Fawns fed the control diet presented higher glucocorticoid and lower testosterone levels then fawns fed the poor diet, suggesting that control fawns faced a higher nutritional stress than those on the poor diet. Similarly to other studies on social mammals, we found no relationship between faecal glucocorticoid levels and social rank, suggesting that social stress was similar for dominant and subordinate fawns during winter. Testosterone levels were not correlated to social rank as found previously in groups of individuals forming stable social hierarchies and maintaining stable dominance relationships. The simultaneous suppression of glucocorticoid and testosterone levels suggests for the first time that young ungulates present a hormonal strategy to prevent fast depletion of limited proteins and fat resources during winter.  相似文献   
456.
Environmental Science and Pollution Research - This paper presents a synthesis of mesoporous silica (MS) from natural clay as a silica source using Pluronic L35 (EO11PO16EO11) as a...  相似文献   
457.
This study reports the optimization of a binary dispersive liquid-liquid microextraction method for the determination of iprodione, procymidone, and chlorflurenol by gas chromatography mass spectrometry. The study was aimed at using two extraction solvents to increase the extraction efficiency of all analytes. The binary solvents recorded results higher than the mono-solvents. After examining the effects of main experimental parameters and their interactions by analysis of variance, 200 μL of binary mixture (dichloromethane and 1,2-dichloroethane), 2.5 mL of ethanol, and 15 s vortex were obtained as optimum parameters. The detection and quantification limits calculated for the analytes were found to be between 0.30–1.6 and 1.0–5.3 ng/mL, respectively. Enhancement in detection power calculated as a ratio of the binary extraction detection limit to the detection limit of direct GC-MS analysis was 105-, 214-, and 233-fold for chlorflurenol, iprodione, and procymidone, respectively. In order to check the accuracy of the developed method, recovery study was performed. Water sampled from a lake and two wastewater samples from treatment facilities were spiked at two concentrations, and the percent recovery calculated for the samples ranged between 87 and 116%. These results confirmed the suitability of the method to real samples for accurate determination of the analytes at trace levels.  相似文献   
458.
Citizen involvement plays an important role in many governmental and municipal attempts towards green transition, reflecting a departure from a deficit model of public communication towards participatory ambitions of engaging citizens. Recently, the notion of co-creation or co-production has gained importance as a way of conceptualizing and organizing citizen involvement. The current study examines how four municipality partners in Sweden and Denmark embark on a common project on citizen involvement and co-creation as an avenue to green transition, addressing private decisions of individual citizens or families where the municipality has no legislative competence. By analysing how several local authorities with different but similar challenges negotiate and jointly identify themselves as agents of citizen involvement, the study offers an upscaling to what may be termed the plura-local level. Analytically, the study takes a discourse approach, combining close readings of texts and talk with an interdiscursive and diachronic analysis.  相似文献   
459.
Bridging the water infrastructure gap has become a major policy concern. In rural areas of Africa, access to water is as much constrained by territorial coverage as it is by the poor conditions of water points due to the difficulty in mobilizing communities for repairs. This paper examines the equity considerations of a rural water and sanitation programme in a district of Mozambique, and their impacts on the achievement of the programme's objectives. Our analysis underlines the contradictions in the conceptualization of equity in the design, planning and implementation of the programme. Even an explicitly pro‐poor strategy can fall short of delivering equity. Our findings stress the fact that overlooking local perception of equity can have a direct impact on the ability of a community to ensure the maintenance of their water points. They call for a careful definition of equity in the design of water programmes, as well as closer attention to this criterion as a precondition to achieving the long‐term objective of the programme.  相似文献   
460.
Source apportionment study was performed, applying principal component analysis to the results of 221 chemical analyses of PM10 and PM2.5 samples collected daily from the industrial (but low traffic) Spanish town of Puertollano over a 14-month period during 2004-2005. Results reveal compositional variations attributable to different mixtures of natural and anthropogenic materials, mainly soil and rock dust (crustal), marine salt (only in PM10), petrochemical refinery emissions, and particles attributed to the combustion of local coal, which is unusually rich in Pb and Sb. During the study period there were 34 pollution episodes when PM10 exceeded 50 tg m(-3), mostly due to winter air temperature inversions, regional atmospheric stagnation, or African dust incursions (North African, NAF days: usually in summer). Whereas the crustal component during NAF episodes averaged 52% with a PM2.5/PM10 ratio of 0.54, this dropped to 29% and a PM2.5/PM10 of 0.67 during non-NAF days when anthropogenic materials predominated. Abnormally enhanced concentrations of pathfinder metallic trace elements provide additional evidence for source apportionment: thus aerosols with raised levels of Pb and Sb are associated with local coal combustion, Ni and V can be linked to petrochemical PM emissions, and Ti, Mn, Rb, and Ce are particularly characteristic of crustal dust incursions.  相似文献   
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